Bangladesh police said Friday they have arrested two suspected members of a banned Islamist group over the brutal killing of an atheist blogger.

Niloy Chakrabarti was hacked to death at his home in Dhaka last Friday by a gang of men, the fourth such murder in Bangladesh this year.

Police said they arrested Saad-al-Nahin and Masum Rana in Dhaka late Thursday, and that both men had confessed to being members of the hardline Ansarullah Bangla Team (ABT), one of two groups that have claimed the killing.

Nahin already faces a charge of attempted murder relating to a 2013 attack on atheist blogger Asif Mohiuddin. He was on bail when he was arrested.

“The police will ask the court for leave to hold them for 10 days for intensive interrogation on Friday,” said a statement.

Chakrabarti was the fourth secular blogger to be killed since February when Bangladeshi-born US citizen Avijit Roy was hacked to death in Dhaka.

In a Facebook post in May, Chakrabarti said he had been followed by two young men, but police had refused to register the complaint and instead advised him to leave the country.

The Bangladesh branch of Al-Qaeda in the Indian Subcontinent (AQIS), Ansar al-Islam, also claimed the killing, according to monitoring group SITE.

Bangladesh has been criticised for failing to do enough to protect its secular bloggers.